Since emotional neuroplasticity is reported to be associated with the pathogenesis of mood disorders, we examined the mechanism of neuroplasticity in an animal model of stress-related disorders, and patients with depression.1)Stress-induced changes in neuroplasticityHippocampal neuroplasticity regulated by neurotrophic factors, plays a role in the development of emotional memory. We examined whether neonatal isolation (NI) or NI with a single restraint stress (SRS) changed the levels of several neurotrophioc factors in the adult rat hippocampus. Whereas NI had no changes in the levels of NGF,BDNF,GDNF,NT-3,IGFR1,IGFR2, or IGFBP2 mRNA, NI + SRS significantly downregulated the levels of GDNF,NGF,IGFR1, and IGFBP2 mRNA. These findings suggest that early adverse experience may affect the development of hippocampal neuroplasticity mediated by neurotrophic factors.2)Changes in fear and hippocampal gene expression in rats subjected to a single prolonged stress (SPS), an animal model of PTSDTo
… More elucidate the molecular pathophysiology of PTSD, we assessed contextual freezing (CF) after fear conditioning and examined the change in hippocampal gene expression involved in the alteration of CF in rats subjected to SPS. The SPS rats showed a significant increase in CF, and cDNA microarray analysis revealed a significant increase in the levels of vesicle associated membrane protein 2(VAMP2). These findings suggest that VAMP2 may be involved in the enhanced CF in SPS rats.3)Emotional neuroplasticity in patients with depressionTo clear the difference for emotional neuroplasticity between depressive patients and healthy controls, we have analyzed the sensory gating system used by Magnetoencepharography(MEG). As a result, depressed patients had the different modulation in sensory gating system by emotional neuroplasticity. These results suggest that the broken sensory gating system in depressed patients might be correlated with vulnerability for stress as the risk for affective disorders. Less